Colon cancer is the third leading cause of cancer in the United States but is the second leading cause of cancer-related deaths. Colon cancer arises from pre-existing colon polyps (adenomas) that occur in as many as 35% of the US population. Colon polyps can either be benign, precancerous or cancerous. Colonoscopy is widely regarded as an excellent screening tool for colon cancer that is increasing in incidence worldwide. According to the literature, a 1% increase in colonoscopy screening results in a 3% decrease in the incidence of colon cancer. The current demand for colonoscopy exceeds the ability of the medical system to provide adequate screening. Despite the increase in colon cancer screening the past few decades, only 55% of the eligible population is screened, falling far short of the recommended 80%, leaving 30 million patients at risk.
Due to the lack of adequate resources, operators performing an colonoscopy typically only sample the largest polyps, exposing the patient to sample bias by typically leaving behind smaller polyps that could advance to colon cancer prior to future colonoscopy. Because of the sample bias, a negative result from the sampled polyps does not ensure the patient is truly cancer-free. Furthermore, operators are not incentivized to remove more polyps since the reimbursement is not based on the number of polyps removed or the adequacy of resection of any particular polyp. Existing polyps removal techniques are cumbersome and time consuming, and not reimbursed at a higher level.
At present, colon polyps are removed using a snare that is introduced into the patient's body via a working channel defined within an endoscope. The tip of the snare is passed around the stalk of the polyp to cut the polyp from the colon wall. Once the cut has been made, the cut polyp lies on the intestinal wall of the patient until it is retrieved by the operator as a sample. To retrieve the sample, the snare is first removed from the endoscope and a biopsy forceps is fed through the same channel of the endoscope to retrieve the sample. The limiting factor for patient access to colonoscopy is the amount of time required to complete procedures where patients have colon polyps.
Accordingly, there is a need for an improved endoscopic tool that increases the precision and speed of polyp removal for biopsy.